CAD中封闭区域的并、交、差运算

UNION,INTERSECTION AND TRIM OPERATIONS OF THE CLOSED REGIONS IN CAD

区域运算在CAD中普遍存在,并且是系统效率的一个瓶颈。本文提出了一种基于交点的凹凸性求封闭区域的并、交、差的算法。首先给出了环、并、交、差、凹凸点的定义；然后描述了算法。该算法的特点是思路简捷,并适合于任意封闭区域。

The region operation occurs conmisong in CAD generally, and is a bottleneck of system efficiency. This paper proposes an algorithm for union, intersection and trim of the closed region, which is based on convex--concave points. The paper detined the loop, union, intersection, trim and convex-concave point and then presents the algorithm, which is simple and suits for any closed regions.